We have a health warning out of florida. Officials are sounding the alarm about a deadly bacteria that breeds in the water. It's killed nine this year. And people with open wounds are being warned to stay out of the water. Abc's matt gutman has the story. Reporter: The bacteria struck silently but swiftly monday. Something that has public health officials here on high alert. I never heard that there was ever even a bacteria in the water. Reporter: Henry was crabbing with his wife, along central florida's intercoastal waterway, when he was apparently affected. When he got home, he thought he just found a spider bite. About 2:00 in the morning, he woke up. His legs were aching. And he felt like there was some sort of a burn on his ankle. Reporter: By 6:00, a man who had been perfectly healthy, had developed lesions all over his body. He's never been diagnosed with any health problems, ever. Reporter: Doctors told henry's wife, patty, the bacteria was eating henry alive. Shutting down his organs. He was dead only 28 hours after going to the hospital. This bacteria creeped through his body like acid. It just -- it was the most horrific thing I've ever seen in my life. It's extremely rare with someone without any medical problems the picture of health, to get this infection and die. Reporter: The bacteria plagues the gulf coast every year, from texas all the way to florida, where officials now believe it has killed nine people so far this year. And infected at least 27 others. I can't imagine going day-by-day without him. Reporter: People with pre-existing liver or kidney conditions are 80-times more likely to be susceptible to this type of bacteria. The cdc says to protect yourself, in water that's brackish like this, wear protective boots. And try to avoid eating raw shellfish. Tom hanks is back on the big

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